Electric transformer



March 4, 1924, 1,486,109

B. W. DAVID ELECTRIC TRANS FORMER Filed April 5-, 1922 u-rr/a/v 0/7 [M'ENTOR.

v I Patented Mar-.4, 1924.

UNITED; STATES I 1,486,109 PATENT ornca.

BRUCE w. navm, or CLEVELAND nnren'rsonro, AssmNoa-T'o WALTER u. soon, or

' CLEVELAND, 01110. 1

ELECTRIC TRANSFORMER.

Application filed April 5, 1922. Serial No. 549,922.

To all whom it may concern:

Be it known that I, BRUCE W. DAVID, a citizen of the United States ofAmerica, residing at Cleveland Heights, in the county 5 of Cuyahoga andState of Ohio, have invented certain new and useful Improve ments inElectric Transformers, of which the following is a specification.

My inventlon relates to improvements in electric transformers, and moreparticularly to the type of amplifiying transformer zb'so that thetransformer coils, which are,

completely surrounded thereby, are protected a ainst external magneticdisturbancep oreover, the laminated core and field members are forcedinto close mechan-v ical contact with the interior of said shell so thatit presents no substantial air gap and aids in closing the magneticlines set up 'in the transformer. v

Further features of advantage and im- 85 provement will be explained inconnection with the accompanying drawings of a simple and compactamplifyin transformer embodying my invention, w erein:

Fi re 1 is a view of said transformer 40 in si e elevation.

Fi 2 isan end' view thereof showing th terminals.

AFi 3 is a cross sectional view on line Fig. 4 is an isometric viewpartially broken away for better illustration of the mode of assemblingthe parts.

Fig. dis a plan view of one of the laminated members, and

Fig. 6 is a Vertical sectional view on line B-B. v

Throughout the several figures of the drawings I have emplo ed the samecharacter of reference to in icate similar parts. As shown in Figs. 3and 4, the transformer coils comprise concentric primary and secondarywindings of cylindrical form, which windings a and b are respectivelyconnected to the binding posts a, a" and b, 12", mounted upon theinsulating head 0.

The paramagnetic laminated members (1, a as shown-in Fig. 5, preferablyare E-shaped in order to form three limbs; the central one of which, (1,comprises a part of the transformer core, while the outer limbs d",together with the connecting cross piece, form the return magneticcircuit when suitably assembled. Thus the transformer coils, areinteriorly filled by inserting the limbs d of the laminationsalternately from either end to afford a sufiicient mass for closing themagnetic lines interiorly and exteriorly of the windings.

These laminations maybe very rapidly assembled with respect to thecoils, as above described, after which the snug-fitting shell e isplaced about the .parts which it com pletely encloses peripherally. Twoscrews f, .f, are inserted through the head 0 and the laminations dhaving been wedged apart laterally along a median plane, as shown in 3,said screws are forced therebetween. and entered within tapped openingsin the base g. This mode of'ass'embling the members serves the doubleurpose of firmly wedging the transformer y with in the shell, which maybe paramagnetic so that there is a negli ible air gap an a securemechanical anc orage, while the attaching screws firmly fix the head andbase rigidly with respect to the transformer- Abcordingly, it will bereadily appreciated that a simple and compact transformer may befabricated at low cost, while affording features of construction andadvantage which are not present in more elaborate and expensiveapparatus.

While I have described a single and extremely simple type ofamplifyingtransformer especially adapted for radio receiving apparatus,it should be understood that m invention is not limited to thesedetails, except as specifically recited in the claims, but relates tothe general class of electric transformers which are ca able ofproduction along the lines define in the foregoing specification. v

Having now described the structural fee.-

tures embodying my invention and the 1 method of practicing the same, Iclaim as new and desire to secure by Letters Patent the following: T t

1. As a new article of manufacture, a transformer of the classdescribed, comprising primary and secondary transformer windings,laminated core members associated therewith, an enclosing shelltherefor, and means for wedging said laminated members securely intoengagement with the interior of the shell, whereby they are held inplace.

2. As a new article of manufacture, an amplifying transformer of theclass described, comprising primary and secondary transformer coils, aplurality of E-shaped laminated core members inserted within and aboutsaid coils, a paramagnetic shell containing the core and coils, andmeans for spreading the exterior portions of the E- shaped laminationsinto wedging engagement with the interior of the shell for retaining thetransformer members securelyin position.

3. As a new article of manufacture, an

amplifying transformer comprising primary and secondary transformercoils, a plurality of E-shaped paramagnetic members inserted within andabout said coils from opposite ends thereof, a close-fittingparamagnetic casing containing said coils and members, end piecesclosing the shell and assembling screws passing through s'ai end piecesand between the E-shaped members, whereby they are spread into closeengagement with the interior of the shell.

t. An electric transformer, comprising primary and secondary transformerwindings, laminated core members associated with said windings, anenclosing shell surrounding the windings and core members,

end pieces positioned to close the shell terminally, and assembling rodsextending through the shell and between the laminated members, wherebythe end pieces are rigidly centered with respect to the body of thetransformer.

5. An electric transformer, comprising primary and secondary transformerwindings, laminated core members having exterior and interior limbsassociated with said windings, an enclosing shell peripherallysurrounding said members and windings, head and base members terminallyclosin the shell, and two assembling rods exten ing between and held bythe displaced laminated members within the shell, adapted to secure thehead and base rigidly with respect to the body of the transformer.

6. An electric transformer, comprising cylindrical concentrictransformer coils, laminated core members of E-shaped contour, saidmembers being inserted alternately from the ends of the coils with theirlimbs enclosed and enclosing said coils, head and base members, and aninterposed shell peripherally enclosing the coils and paramagneticmembers, and assembling screws passing through the head and base membersand wedging the laminated members securely into engagementwith theinterior of the'shell.

7. The herein described method of constructing transformers, whichconsists in providing their laminated core members with a snug-fittingenclosing shell, assembling the core members in unconnected relationperipherally, inserting them within said shell, and spreading the coremembers into wedging enga ement with the interior of the shell, wherebythey are securely retained in position. I

8. The herein described method of constructing transformers, whichconsists in providing the transformer coils wlth peripherally laminatedmembers extending within and about said coils, insertin said parts asassembled within a snugly-fitting enclosing casing, and wedging thelaminated members apart into close engagement with the interior of thecasing, whereby they arc retained in place.

In testimony whereof I do now affix my signature.

BRUCE W. DAVID.

